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Finding the Fourth Proportional to 65.30, 90.53 and 61.65

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Solution

The fourth proportional to 65.30, 90.53 and 61.65 is: 85.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.30 : 90.53 = 61.65 : x
  2. Step 2: Convert to fraction form
    65.30/90.53 = 61.65/x
  3. Step 3: Cross multiply
    65.30x = 90.53 × 61.65
  4. Step 4: Simplify right side
    65.30x = 5,580.87
  5. Step 5: Solve for x
    x = 5,580.87/65.30
  6. Step 6: Final answer
    x = 85.47

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.